LT3593
1MHz White LED Driver with
Output Disconnect and One
Pin Current Programming
FEATURES
DESCRIPTION
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The LT®3593 is a step-up DC/DC converter designed to
drive up to ten white LEDs in series from a Li-Ion cell.
Series connection of the LEDs provides identical LED
currents and eliminates the need for ballast resistors. The
device features a unique high side LED current sense that
enables the part to function as a “one wire current source”
where the low side of the LED string can be returned to
ground anywhere.
n
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Drives Up to Ten White LEDs from a 3V Supply
One Pin Shutdown and Current Programming
LEDs Disconnected in Shutdown
32:1 Linear Brightness Control Range
VIN Range: 2.7V to 5.5V
±5% Output Current Accuracy at Full Scale
Low Shutdown Current: 3μA
1MHz Switching Frequency
Requires Only 1μF Output Capacitor
Low Profile 6-Lead DFN (2mm × 2mm × 0.75mm)
and 6-Lead SOT-23 Packages
APPLICATIONS
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Additional features include output disconnect in shutdown,
open LED protection and 1-pin shutdown/LED current
control. The CTRL pin is toggled to adjust the LED current
via an internal counter and a 5-bit DAC.
The LT3593 switches at 1MHz, allowing the use of tiny
external components. Constant frequency switching results in low input noise and a small output capacitor. The
LT3593 is available in the 6-lead DFN (2mm × 2mm) as
well as the 6-lead SOT-23 packages.
Cell Phones
Digital Cameras
PDAs, Handheld Computers
MP3 Players
GPS Receivers
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
Li-Ion Driver for Ten White LEDs
90
10μH
1μF
1μF
VIN
SW
CAP
LT3593
SHUTDOWN AND
CURRENT CONTROL
CTRL
LED
GND
VIN = 3.6V
10 LEDs
80
EFFI CIENCY (%)
VIN
3V TO 5V
Conversion Efficiency
70
60
50
40
30
0
5
10
15
LED CURRENT (mA)
20
3593 TA01b
3593 TA01a
3593f
1
LT3593
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Input Voltage...............................................................6V
CTRL Voltage ..............................................................6V
SW Voltage ...............................................................45V
CAP Voltage ..............................................................45V
LED Voltage ..............................................................45V
Operating Junction Temperature Range
(Note 2).................................................... –40°C to 85°C
Maximum Junction Temperature........................... 125°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
TSOT Package................................................... 300°C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
6 SW
VIN 1
GND 2
CTRL 3
7
5 CAP
4 LED
CTRL 1
6 LED
GND 2
5 CAP
VIN 3
4 SW
S6 PACKAGE
6-LEAD PLASTIC TSOT-23
DC PACKAGE
6-LEAD (2mm × 2mm) PLASTIC DFN
TJMAX = 125°C, θJA = 192°C/W
TJMAX = 125°C, θJA = 106°C/W
EXPOSED PAD (PIN 7) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT3593EDC#PBF
LT3593EDC#TRPBF
LDBR
6-Lead (2mm × 2mm) Plastic DFN
–40°C to 85°C
LT3593ES6#PBF
LT3593ES6#TRPBF
LTDBS
6-Lead Plastic TSOT-23
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 3.6V, VCTRL = 3.6V, unless otherwise specified.
PARAMETER
CONDITIONS
Operating Voltage Range
Supply Current
MIN
TYP
2.7
Not Switching; During Current Programming
MAX
5.5
300
CTRL = 0
UNITS
V
μA
3
10
Switching Frequency
0.85
1
1.15
Maximum Duty Cycle
92
94
%
Switch Current Limit
550
700
mA
250
mV
Switch VCESAT
ISW = 250mA
μA
MHz
3593f
2
LT3593
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 3.6V, VCTRL = 3.6V, unless otherwise specified.
PARAMETER
CONDITIONS
Switch Leakage Current
VSW = 30V
LED Pin Voltage Drop (VCAP – VLED)
ILED = 20mA
LED Pin Leakage Current
CTRL = 0, VCAP = 35V
MIN
TYP
MAX
1
250
μA
mV
1
CTRL High Threshold
UNITS
μA
1.6
V
CTRL Low Threshold
0.4
V
CTRL tPW
Programming Pulse Width (Note 3)
250
CTRL tSD
Time from CTRL = 0 to Shutdown
95
128
200
μs
CTRL tEN
Time from CTRL = 1 to Enable
95
128
200
μs
Full-Scale LED Current
VCAP = 16V
VCAP = 16V
19
18.5
20
20
21
21.5
mA
mA
LED Current Programming Resolution
Linear Increments
l
LED Current Limit
CTRL Pin Bias Current
ns
625
μA
45
mA
VCTRL = 5.5V
Overvoltage Protection
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
l
36
38
1
μA
40
V
Note 2: The LTC3593E is guaranteed to meet performance specifications
from 0°C to 85°C operating junction temperature range. Specifications
over the –40°C to 85°C operating junction temperature range are assured
by design, characterization and correlation with statistical process
controls.
Note 3: Guaranteed by design.
3593f
3
LT3593
TYPICAL PERFORMANCE CHARACTERISTICS
Switch Saturation Voltage
(VCESAT)
100°C
400
25°C
300
–50°C
200
3.25
100°C
4
25°C
–50°C
3
2
1
100
0
100
300
500
200
400
SWITCH CURRENT (mA)
600
LED Pin Voltage Drop
(VCAP – VLED)
2
3
4
VIN (V)
6
5
LED PIN CURRENT LIMIT (mA)
100°C
200
25°C
150
–50°C
100
50
5
2.00
10
15
LED CURRENT (mA)
20
3
4
VIN (V)
6
5
3593 G03
Switching Current Limit vs
Temperature
750
VIN = 3.6V
VIN = 3.6V
VCAP = 16V
45
44
43
42
–50
2
3593 G02
46
VIN = 3.6V
VCAP = 16V
0
–50°C
2.50
LED Pin Current Limit
300
250
25°C
2.75
SWITCH CURRNET LIMIT (mA)
0
100°C
3.00
2.25
3593 G01
VCAP – VLED (mV)
QUIESCENT CURRENT (mA)
SHUTDOWN CURRENT (μA)
SWITCH SATURATION VOLTAGE (mV)
3.50
5
500
0
Quiescent Current (VCTRL = 3.6V)
Shutdown Current (VCTRL = 0V)
6
600
0
TA = 25°C unless otherwise specified.
–25
0
25
50
TEMPERATURE (°C)
75
3593 G04
100
700
650
600
550
–50
–25
0
25
50
TEMPERATURE (°C)
3593 G05
75
100
3593 G06
Transient Response
Switching Waveform
VCTRL
5V/DIV
IL
200mA/DIV
IL
200mA/DIV
VCAP
200mV/DIV
AC COUPLED
VCAP
10V/DIV
VSW
20V/DIV
VIN = 3.6V
1μs/DIV
FRONT PAGE
APPLICATION CIRCUIT
3393 G07
VIN = 3.6V
200μs/DIV
FRONT PAGE
APPLICATION CIRCUIT
3393 G08
3593f
4
LT3593
TYPICAL PERFORMANCE CHARACTERISTICS
Open-Circuit Output Clamp
Voltage
100°C
–50°C
37
3
2
4
VIN (V)
5
6
8
7
6
5
4
3
2
2.0
3.5
6
5
4
3
0
25
50
TEMPERATURE (°C)
4.0 4.5
VIN (V)
5.0
5.5
75
0
25
50
TEMPERATURE (°C)
75
100
3593 G11
LED Current vs CTRL Strobe
Pulses
VIN = 3.6V
10LEDS
15
1050
1000
950
10
5
900
0
–25
50
0
25
TEMPERATURE (°C)
75
100
0
32
8
16
24
NUMBER OF CTRL STROBES
3593 G14
3593 G13
Full-Scale Current vs
Temperature
Full-Scale Current vs VCAP
21.0
21.0
10 LEDs
FULL SCALE CURRENT (mA)
VIN = 3.6V
10LEDS
20.5
LED CURRENT (mA)
20.0
20.0
19.5
19.5
19.0
3.0
–25
VIN = 3.6V
850
–50
100
20.5
LED CURRENT (mA)
36
–50
6.0
1100
Full-Scale Current vs VIN
19.0
2.5
37
3593 G10
3593 G12
21.0
38
20
1150
SWITCHING FREQUENCY (kHz)
INPUT CURRENT OUTPUT OPEN-CIRCUIT (mA)
3.0
39
Switching Frequency vs
Temperature
7
–25
2.5
3593 G09
VIN = 3.6V
2
–50
VIN = 3.6V
9
Input Current in Output
Open-Circuit vs Temperatue
8
40
LED CURRENT (mA)
36
10
OPEN-CIRCUIT CLAMP VOLTAGE (V)
INPUT CURRENT OUTPUT OPEN-CIRCUIT (mA)
OPEN-CIRCUIT CLAMP VOLTAGE (V)
39
38
Open-Circuit Output Clamp
Voltage vs Temperature
Input Current in Output Open
Circuit
40
25°C
TA = 25°C unless otherwise specified.
3.5
4.0 4.5
VIN (V)
5.0
5.5
6.0
3593 G15
5
10
15
20
25
VCAP (V)
30
35
3593 G16
20.5
20.0
19.5
19.0
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
3593 G17
3593f
5
LT3593
PIN FUNCTIONS
(DFN/TSOT)
VIN (Pin 1/Pin 3): Input Supply Pin. Must be locally bypassed with a 1μF X5R or X7R type ceramic capacitor.
The pin must be held high after the final desired positive
strobe edge. The data is transferred after a 128μs (typ)
delay. The part can be reprogrammed to a different value
after it has been enabled, however the current will change
to the new value after 128μs. If CTRL is held low for longer
than 128μs (typ), the part will go into shutdown.
GND (Pin 2/Pin 2): Ground Pin. Connect directly to local
ground plane.
SW (Pin 6/Pin 4): Switch Pin. Connect inductor between
this pin and the VIN pin. Minimize inductance at this pin
to minimize EMI.
LED (Pin 4/Pin 6): LED Pin. An internal switch connects
this pin to CAP. The top of the LED string is connected
to this pin. When the part is in shutdown, the LED pin is
switched off from CAP so no current runs through the
LEDs. The switch is also used to sense the LED current
when the part is on.
CAP (Pin 5/Pin 5): Output Pin. Connect to output capacitor. Minimize trace between this pin and output capacitor
to reduce EMI.
CTRL (Pin 3/Pin 1): Current Control and Shutdown Pin.
This pin is used to program the LED output current. This
pin is strobed up to 32 times to decrement the internal
5-bit DACs from full-scale to 1LSB. The counter will stop
at 1LSB if the strobing continues beyond 32 counts.
Exposed Pad (Pin 7/NA): Ground. The Exposed Pad must
be soldered to the PCB.
BLOCK DIAGRAM
1
6
VIN
SW
PWM
COMP
–
DRIVER
A2
R
+
S
Q1
Q
CAP
OVERVOLTAGE
PROTECTION
5
+
+
–
R
A3
–
M2
M1
RAMP
GENERATOR
VREF
1.24V
OSCILLATOR
5-BIT
LINEAR DAC
–
SHDN
SHDN
LED
A1
4
+
RC
CC
5-BIT
COUNTER
GND
7
2
SHDN
CTRL
3
3593 F01
PIN NUMBERS REFER TO DFN PACKAGE. REFER TO PIN CONFIGURATION FOR TSOT PIN NUMBERS
Figure 1. Block Diagram
3593f
6
LT3593
OPERATION
The LT3593 uses a constant frequency, current mode
control boost scheme to provide excellent line and load
regulation. Operation can be best understood by referring
to the Block Diagram in Figure 1.
Output Disconnect
An internal switch connects between the CAP pin and the
LED pin. The top of the LED string is connected to the
LED pin. The string can be terminated to ground or to
VIN if a low number of LEDs are driven. When the part is
in shutdown, the switch is off; allowing no current to run
through the LEDs.
Current Programming
The LED current can be set to 32 different values
(625μA – 20mA) by strobing the CTRL pin. A 5-bit
counter is decremented by 1 on a CTRL pin rising edge,
reducing the programmed current by 625μA each time.
The desired current can be calculated by:
ILED = 20mA – (N – 1) • 625μA
where N is the number of rising edges. When the desired
current setting is reached, the CTRL pin must stay high.
128μs after the last rising edge on the CTRL pin, the
regulator will enable the output and start to regulate the
LED current to the programmed value. Figure 2 shows
an example of how the part can be programmed.
If a different current is desired, the CTRL pin can be strobed
again. The first falling edge will reset the internal register
to the 20mA setting. While the new current is being programmed, the device will continue to regulate the previously
programmed value until the CTRL pin has remained high
for at least 128μs, at which time the regulated current will
slew to the newly programmed value. Figure 3 shows how
to program a new LED current level.
If the CTRL pin is held low for longer than 128μs, the part
will go into the shutdown mode.
CTRL
FULL CURRENT
20mA
CTRL
17.5mA
CTRL
15mA
CTRL
12.5mA
3593 F02
Figure 2. Current Programming
128μs
128μs
128μs
CTRL
20mA
20mA
17.5mA
LED
CURRENT
17.5mA
SHDN
3593 F03
Figure 3. Current Programming and Shutdown Timing
3593f
7
LT3593
APPLICATIONS INFORMATION
Inductor Selection
A 10μH inductor is recommended for most LT3593 applications. Although small size and high efficiency are
major concerns, the inductor should have low core losses
at 1MHz and low DCR (copper wire resistance). Some
inductors in this category with small size are listed in
Table 1. The efficiency comparison of different inductors
is shown in Figure 4.
Table 2 shows a list of several ceramic capacitor manufacturers. Consult the manufacturers for detailed information
on their entire selection of ceramic parts.
Table 2. Recommended Ceramic Capacitor Manufacturers
Taiyo Yuden
AVX
Murata
Table 1. Recommended Inductors
Kemet
L
(μH)
10
10
10
DCR
(Ω)
0.24
0.44
0.45
CURRENT
RATING
(mA)
650
450
500
VLF4012AT-100M
VLF3010AT-100M
10
10
0.20
0.58
500
490
TDK
DE2812-1098AS-100M
DB3015C-1068AS-100M
10
10
0.29
0.38
580
400
TOKO
PART
LQH43CN100
LQH32CN100
NR3010T100M
VENDOR
Murata
Taiyo Yuden
90.00
EFFI CIENCY (%)
80.00
70.00
40.00
30.00
0.00
Diode Selection
Schottky diodes, with their low forward voltage drop and
fast reverse recovery, are the ideal choices for LT3593 applications. The forward voltage drop of a Schottky diode
represents the conduction losses in the diode, while the
diode capacitance (CT or CD) represents the switching
losses. For diode selection, both forward voltage drop and
diode capacitance need to be considered. Schottky diodes
with higher current ratings usually have lower forward
voltage drop and larger diode capacitance, which can
cause significant switching losses at the 1.0MHz switching
frequency of the LT3593. A Schottky diode rated at 400mA
to 500mA is sufficient for most LT3593 applications. Some
recommended Schottky diodes are listed in Table 3.
Table 3. Recommended Schottky Diodes
60.00
50.00
(408) 573-4150
www.t-yuden.com
(803) 448-9411
www.avxcorp.com
(714) 852-2001
www.murata.com
(408) 986-0424
www.kemet.com
NR3010T100M
VLF4012-AT-100MR50
LQH43CN100K03
VLF3010AT-100MR49
LQH32CN100K53
DB3015C-1068AS-100M
10.00
5.00
15.00
LED CURRENT (mA)
20.00
PART
NUMBER
FORWARD VOLTAGE
DIODE
CURRENT DROP CAPACITANCE
(mA)
(V)
(pF)
MANUFACTURER
CMDSH05-4
500
0.47 at
500mA
50 at 1V
CMMSH1-40
1000
0.55 at
1A
80 at 4V
ZLL5400
520
0.50 at
400mA
15 at 30V
Zetex
631-543-7100
www.zetex.com
PMEG4005AEA
500
0.47 at
500mA
50 at 1V
Phillips
+3140 27 24825
www.semiconductors.
phillips.com
3593 F04
Figure 4. Efficiency Comparison of Different Inductors
Capacitor Selection
The small size of ceramic capacitors makes them ideal
for LT3593 applications. Use only X5R and X7R types
because they retain their capacitance over wider voltage
and temperature ranges than other types such as Y5V or
Z5U. A 1μF input capacitor and a 1μF output capacitor are
sufficient for most applications.
Central
631-435-1110
www.centralsemi.com
3593f
8
LT3593
APPLICATIONS INFORMATION
Overvoltage Protection
Low Input Voltage Applications
The LT3593 has an internal open-circuit protection circuit.
In the case of an output open circuit, when the LEDs are
disconnected from the circuit or the LEDs fail open, VCAP
is clamped at 38V. The LT3593 will then switch at a very
low frequency to minimize input current. VCAP and input
current during output open circuit are shown in the Typical
Performance Characteristics. Figure 5 shows the transient
response when the LEDs are disconnected.
The LT3593 can be used in low input voltage applications.
The input supply voltage to the LT3593 must be 2.7V or
higher, but the inductor can be run off a lower battery
voltage. This technique allows the LEDs to be powered off
two alkaline cells. Most portable devices have a 3.3V logic
supply voltage which can be used to power the LT3593.
The LEDs can be driven straight from the battery, resulting
in higher efficiency.
Figure 6 shows three LEDs powered by two AA cells.
The battery is connected to the inductors and the chip is
powered off a 3.3V logic supply voltage.
2 AA CELLS
2V TO 3.2V
3.3V
IL
200mA/DIV
L1
10μH
C1
1μF
C3
1μF
SHUTDOWN AND
CURRENT CONTROL
D1
C2
1μF
SW
VIN
CAP
LT3593
CTRL
LED
GND
VCAP
20V/DIV
VSW
20V/DIV
3593 F06
3593 F05
VIN = 3.6V
400μs/DIV
FRONT PAGE
LEDs DISCONNECTED
APPLICATION CIRCUIT
AT THIS INSTANT
Figure 5. Output Open-Circuit Waveform
C1: TAIYO YUDEN EMK107B5105MA
C2: MURATA GRM31MR71H105KA88
L1: MURATA LQH43CN100
D1: CENTRAL CMDSH05-4
Figure 6. Two AA Cells to Three White LEDs
3593f
9
LT3593
APPLICATIONS INFORMATION
Board Layout Considerations
As with all switching regulators, careful attention must
be paid to the PCB layout and component placement. To
prevent electromagnetic interference (EMI) problems,
proper layout of high frequency switching paths is essential.
Minimize the length and area of all traces connected to the
Switching node pin (SW). Keep the sense voltage pins (CAP
and LED) away from the switching node. Place C2 next to
the CAP pin. Always use a ground plane under the switching
regulator to minimize interplane coupling. Recommended
component placement is shown in Figure 7.
L1
L1
VIN
VIN
C1
2
CTRL
3
7
D1
D1
4
3
5
5
2
4
6
1
6
1
C1
CTRL
GND
GND
C2
C2
3593 F07
DFN Package
TSOT-23 Package
Figure 7. Recommended Component Placement
3593f
10
LT3593
TYPICAL APPLICATIONS
Li-Ion Driver for One White LED
Conversion Efficiency
70
C2
1μF
C1
1μF
VIN
D1
SW
EFFICIENCY (%)
VIN
3V TO 5V
L1
10μH
60
VIN = 3.6V
1 LED
50
40
30
CAP
20
LT3593
SHUTDOWN AND
CURRENT CONTROL
LED
CTRL
GND
10
0
5
3593 TA02a
10
15
LED CURRENT (mA)
20
3593 TA02b
C1: TAIYO YUDEN EMK107BJ105MA
C2: TAIYO YUDEN GMK316BJ105ML
L1: MURATA LQH43CN100
D1: CENTRAL CMDSH05-4
Li-Ion Driver for Two White LED
Conversion Efficiency
80
C2
1μF
C1
1μF
VIN
D1
SW
EFFICIENCY (%)
VIN
3V TO 5V
L1
10μH
70
VIN = 3.6V
2 LEDs
60
50
40
CAP
30
LT3593
SHUTDOWN AND
CURRENT CONTROL
LED
CTRL
GND
20
3593 TA03a
0
5
10
15
LED CURRENT (mA)
20
3593 TA03b
C1: TAIYO YUDEN EMK107BJ105MA
C2: TAIYO YUDEN GMK316BJ105ML
L1: MURATA LQH43CN100
D1: CENTRAL CMDSH05-4
3593f
11
LT3593
TYPICAL APPLICATIONS
Li-Ion Driver for Three White LEDs
C1
1μF
VIN
CTRL
80
C2
1μF
SW
CAP
LT3593
SHUTDOWN AND
CURRENT CONTROL
VIN = 3.6V
3 LEDs
D1
EFFICIENCY (%)
VIN
3V TO 5V
Efficiency
90
L1
10μH
LED
GND
70
60
50
40
3593 TA04a
30
C1: TAIYO YUDEN EMK107BJ105MA
C2: TAIYO YUDEN GMK316BJ105ML
L1: MURATA LQH43CN100
D1: CENTRAL CMDSH05-4
0
5
C1
1μF
VIN
Efficiency
90
D1
C2
1μF
SW
CAP
LT3593
SHUTDOWN AND
CURRENT CONTROL
CTRL
LED
GND
VIN = 3.6V
4 LEDs
80
EFFICIENCY (%)
VIN
3V TO 5V
20
3593 TA04b
Li-Ion Driver for Four White LEDs
L1
10μH
10
15
LED CURRENT (mA)
70
60
50
40
3593 TA05a
30
C1: TAIYO YUDEN EMK107BJ105MA
C2: TAIYO YUDEN GMK316BJ105ML
L1: MURATA LQH43CN100
D1: CENTRAL CMDSH05-4
0
5
VIN
D1
LT3593
SHUTDOWN AND
CURRENT CONTROL
CTRL
80
C2
1μF
SW
CAP
EFFICIENCY (%)
C1
1μF
Efficiency
90
L1
10μH
LED
GND
20
3593 TA05b
Li-Ion Driver for Six White LEDs
VIN
3V TO 5V
15
10
LED CURRENT (mA)
VIN = 3.6V
6 LEDs
70
60
50
40
30
3593 TA06a
0
5
15
10
LED CURRENT (mA)
20
3593 TA06b
C1: TAIYO YUDEN EMK107BJ105MA
C2: TAIYO YUDEN GMK316BJ105ML
L1: MURATA LQH43CN100
D1: CENTRAL CMDSH05-4
3593f
12
LT3593
TYPICAL APPLICATIONS
Li-Ion Driver For Ten White LEDs
L1
10μH
VIN = 3.6V
10 LEDs
D1
80
C1
1μF
VIN
C2
1μF
SW
CAP
EFFICIENCY (%)
VIN
3V TO 5V
Efficiency
90
LT3593
SHUTDOWN AND
CURRENT CONTROL
CTRL
LED
70
60
50
GND
40
30
0
5
15
10
LED CURRENT (mA)
20
3593 TA07b
3593 TA07a
C1: TAIYO YUDEN EMK107BJ105MA
C2: MURATA GRM31MR71H105KA88
L1: MURATA LQH43CN100
D1: CENTRAL CMDSH05-4
Li-Ion Driver For Ten White LEDs
90
L1
22μH
D1
80
C1
1μF
VIN
C2
2.2μF
SW
CAP
EFFICIENCY (%)
VIN
3V TO 5V
Efficiency
LT3593
SHUTDOWN AND
CURRENT CONTROL
CTRL
LED
VIN = 3.6V
10 LEDs
70
60
50
GND
40
30
0
5
15
10
LED CURRENT (mA)
20
3593 TA08b
3593 TA08a
C1: TAIYO YUDEN EMK107BJ105MA
C2: MURATA GRM31CR71H225KA88
L1: MURATA LQH43CN220
D1: CENTRAL CMDSH05-4
3593f
13
LT3593
PACKAGE DESCRIPTION
DC Package
6-Lead Plastic DFN (2mm × 2mm)
(Reference LTC DWG # 05-08-1703)
0.675 ±0.05
2.50 ±0.05
1.15 ±0.05 0.61 ±0.05
(2 SIDES)
PACKAGE
OUTLINE
0.25 ± 0.05
0.50 BSC
1.42 ±0.05
(2 SIDES)
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
R = 0.115
TYP
0.56 ± 0.05
(2 SIDES)
0.38 ± 0.05
4
6
2.00 ±0.10
(4 SIDES)
PIN 1 BAR
TOP MARK
(SEE NOTE 6)
PIN 1
CHAMFER OF
EXPOSED PAD
3
0.200 REF
0.75 ±0.05
1
(DC6) DFN 1103
0.25 ± 0.05
0.50 BSC
1.37 ±0.05
(2 SIDES)
0.00 – 0.05
BOTTOM VIEW—EXPOSED PAD
NOTE:
1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WCCD-2)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE
TOP AND BOTTOM OF PACKAGE
3593f
14
LT3593
PACKAGE DESCRIPTION
S6 Package
6-Lead Plastic TSOT-23
(Reference LTC DWG # 05-08-1636)
0.62
MAX
2.90 BSC
(NOTE 4)
0.95
REF
1.22 REF
3.85 MAX 2.62 REF
1.4 MIN
2.80 BSC
1.50 – 1.75
(NOTE 4)
PIN ONE ID
RECOMMENDED SOLDER PAD LAYOUT
PER IPC CALCULATOR
0.30 – 0.45
6 PLCS (NOTE 3)
0.95 BSC
0.80 – 0.90
0.20 BSC
0.01 – 0.10
1.00 MAX
DATUM ‘A’
0.30 – 0.50 REF
0.09 – 0.20
(NOTE 3)
1.90 BSC
S6 TSOT-23 0302 REV B
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DRAWING NOT TO SCALE
3. DIMENSIONS ARE INCLUSIVE OF PLATING
4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR
5. MOLD FLASH SHALL NOT EXCEED 0.254mm
6. JEDEC PACKAGE REFERENCE IS MO-193
3593f
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
15
LT3593
TYPICAL APPLICATION
Li-Ion Driver for Six LEDs
90
L1
10μH
C1
1μF
VIN
D1
SW
CAP
LT3593
SHUTDOWN AND
CURRENT CONTROL
CTRL
80
C2
1μF
EFFICIENCY (%)
VIN
3V TO 5V
Efficiency
LED
GND
VIN = 3.6V
6 LEDs
70
60
50
40
30
0
5
10
15
LED CURRENT (mA)
20
3593 TA06b
3593 TA06a
C1: TAIYO YUDEN EMK107BJ105MA
C2: TAIYO YUDEN GMK316BJ105ML
L1: MURATA LQH43CN100
D1: CENTRAL CMDSH05-4
RELATED PARTS
PART NUMBER
LT1932
LTC3205
DESCRIPTION
Constant Current, 1.2MHz, High Efficiency White LED
Boost Regulator
Constant Current, 1.2MHz, High Efficiency White LED
Boost Regulator
Low Noise, 2MHz Regulated Charge Pump White
LED Driver
Low Noise, 2MHz Regulated Charge Pump White
LED Driver
Low Noise, 1.7MHz Regulated Charge Pump White
LED Driver
Low Noise, 1.5MHz Regulated Charge Pump White
LED Driver
High Efficiency, Multidisplay LED Controller
LTC3210
Low Noise Charge Pump LED Controller
LT3465/LT3465A
LT3491
Constant Current, 1.2MHz/2.7MHz, High Efficiency
White LED Boost Regulator with Integrated Schottky
Diode
Dual Full Function, 2MHz Diodes White LED Step-Up
Converter with Built-In Schottkys
Dual 1.3A White LED Converter with 1000:1 True
Color PWM Dimming
White LED Driver with Integrated Schottky
LT3591
White LED Driver with Integrated Schottky
LT1937
LTC®3200
LTC3200-5
LTC3201
LTC3202
LT3466/LT3466-1
LT3486
COMMENTS
Up to 8 White LEDs, VIN: 1V to 10V, VOUT(MAX) = 34V, IQ = 1.2mA,
ISD < 1μA, ThinSOTTM Package
Up to 4 White LEDs, VIN: 2.5V to 10V, VOUT(MAX) = 34V, IQ = 1.9mA,
ISD < 1μA, ThinSOT and SC70 Packages
Up to 6 White LEDs, VIN: 2.7V to 4.5V, IQ = 8mA, ISD < 1μA, MS Package
Up to 6 White LEDs, VIN: 2.7V to 4.5V, IQ = 8mA, ISD < 1μA, ThinSOT
Package
Up to 6 White LEDs, VIN: 2.7V to 4.5V, IQ = 6.5mA, ISD < 1μA, MS Package
Up to 8 White LEDs, VIN: 2.7V to 4.5V, IQ = 5mA, ISD < 1μA, MS Package
Up to 4 (Main), 2 (Sub) and RGB, VIN: 2.8V to 4.5V, IQ = 50μA, ISD < 1μA,
24-Lead QFN Package
Up to 4 White LEDs and One High current CAM LED, VIN: 2.9V to 4.5V,
IQ = 4.5mA, ISD < 6μA, UD Package
Up to 6 White LEDs, VIN: 2.7V to 16V, VOUT(MAX) = 34V, IQ = 1.9mA,
ISD < 1μA, ThinSOT Package
Up to 20 White LEDs, VIN: 2.7V to 24V, VOUT(MAX) = 39V,
DFN and TSSOP-16 Packages
Drives Up to 16 100mA White LEDs. VIN: 2.5V to 24V, VOUT(MAX) = 36V,
DFN and TSSOP Packages
Up to 6 White LEDs, VIN: 2.5V to 12V, IQ = 2.6mA, ISD < 10μA, SC70 and
2mm × 2mm DFN Packages
Up to 10 White LEDs, VIN: 2.5V to 12V, IQ = 4mA, ISD < 11μA,
3mm × 2mm DFN Package
ThinSOT is a trademark of Linear Technology Corporation.
3593f
16 Linear Technology Corporation
LT 0308 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2008